Solve for $x$ and $y$ by deriving an expression for $x$ from the second equation, and substituting it back into the first equation. $\begin{align*}3x-8y &= -2 \\ 7x-7y &= 7\end{align*}$
Begin by moving the $y$ -term in the second equation to the right side of the equation. $7x = 7y+7$ Divide both sides by $7$ to isolate $x$ $x = {y + 1}$ Substitute this expression for $x$ in the first equation. $3({y + 1}) - 8y = -2$ $3y + 3 - 8y = -2$ Simplify by combining terms, then solve for $y$ $-5y + 3 = -2$ $-5y = -5$ $y = 1$ Substitute $1$ for $y$ in the top equation. $3x-8( 1) = -2$ $3x-8 = -2$ $3x = 6$ $x = 2$ The solution is $\enspace x = 2, \enspace y = 1$.